Hair dye and chemical straightener use and breast cancer risk (2019)

My response to this article was maybe not well formulated. I just wanted to voice that the study observed different effects related to the type of dying: semi versus permanent, dark vs light, which points to the role of the developer formulation. Unless the coloring chemicals are different between semi and permanent too.

I think we agree that we still have no idea about what has been measured here.

Sometimes they also apply heat, you can clearly smell it then.

Yes, you are right. I should have said hair shaft instead of follicle.

> TNBC is not really a direct category of breast cancer. It's a catch all for "any breast cancer that doesn't have one of the main three targettable handles associated with breast cancer"

> In many cases, it could even be a cancer "from some other organ" that winds up in the breast and happens to, even by chance (not growing in the breast because it's a favorable environment), grow there.

That would imply metastasis, would it not? By which, the originating organ of the tumour could be determined by examining the samples from the initial biopsy. The doctor said that in the case of TNBC there is no hormone expression, which makes it differ from other BC types, and why a more aggressive chemo regime is required for this diagnosis.

I was there, at her second-opinion encounter. Nothing was mentioned about it possibly originating from another organ. She had had repeated body scans, blood work, all that one can imagine. I'm not saying you are wrong, I am saying there was not a single mention in any part of the treatment nor received "coping" literature that this could have come from another organ.

You're rolling the dice every time you do something that increases your cancer risk. Cancer doesn't have some sort of threshold where you get it.

So yeah, it could have caused it. Is it the likely cause? Maybe not.

Cancer is a numbers game. Unlike say, blackjack, you only know about certain risk factors. Many are unknown.

With skin cancer, getting a sunburn every two years triples your risk of developing melanoma. With the fairest skin types, even a single severe burn can increase risk if melanoma. Other skin cancers tend to result from constant exposure over time.

I don’t know much about this scenario with hair product. But if you have some other risk factors, it’s not unreasonable that a single exposure may result in a bad outcome.

This is a fantastic way to respond to an old comment.

Really interesting analysis. Thanks for sharing this!

I must be too active on HN when my username is showing up in these lists.

A flawed model to understand this would be to picture a hexagon with nodes on the vertices. Then, consider a hexagon with one main node in the centre.

When electrons are tightly bound into nodes in and between the vertices, they are energetically ‘stable’. They, therefore, do not like change.

When electrons are shared equally between all nodes and are mobile, they could be considered to be ‘more active’. As the electrons are not tightly bound, it is ‘all to play for’ and some change in state may be accommodated.

The optical activity described occurs because the equally shared, ‘central node’ electrons are ‘free-er’ and have the flexibility to accept unusual states. This is because in the multi-node model, the electrons may be considered tightly bound to each node and so any the effect of any change in the state of a given electron is highly concentrated and local.

In the shared electron central node model the electrons are ‘more mobile’ and so any change in state has a distributed and shared effect across all electrons, rather than only those in a given node of the multi modal model.

To emit light, an electron must absorb enough energy to reach ‘the next level’. In the multi nodal model, the next level is extremely far away and may require so much energy that the molecule will disintegrate rather than emit light.

In the equally shared central node model, the next level is ‘accessible’ in that, whilst unstable, the mobile bulk of electrons in the molecule can accommodate the change and radiate the excess away.

The exact colour of light is determined by the energy required to reach the next level, in most cases. This is a consequence of the delocalisation of electrons in dyes, which may be considered as following the shared central node model. A further consequence is increased reactivity.

This explanation should be considered poor and ignores a lot of nuance and theory (whilst relying on a hazy memory). Likewise, it neglects to explain intriguing phenomena such as the anion-pi interaction. In any case, I hope it is not ‘too wrong’ and helps!